Extension cord set



` April 7, 1953 J. w. BARNES 2,634,309

EXTENSION CORD SET Filed Nov. 18, 1948 n v. '11.11111 v-l,

` n f 3 9 /NVEA/ro/P 1:1- 7 l BMMJZW Attorneys Patented Apr. 7, 1953UNITED STATES PATENT OFFICE EXTENSION CORD SET John `Wrarnes, AnnArbor,ltic'h.,` assigner, to Argus Cameras, Inc., a corporationof.Micliigan Application November 18, 1948SerialNo..60`,740

1 Claim.

Thisz'inventon Vrelates to a special extension cordziset; for:photographic purposes to enablev multiple: ash gunsv toA be synchronizedwith a camera,y

The' invention iszproposed to satisfy a demand fromphotographers forbetter and more artistic lighting.' ofi subjects to be photographed. Itenables several flash lamps to be fired with actuationzof thecamerashutter toilluminate the subject: from desired angles and eliminate theflat lighting effects often encountered where only asingleash gun isred.

ItListhe primary. object of my invention to pro--Y vide a novelextension cord structure adapting several flash lamp units to acamerahaving a shutter. controlled switch. The units may be mounted-inlvarious combinations, anda partie Figurev 1 is a diagrammatic viewillustrating one usageof. the. extension of. the invention;

Figure 2 is an enlarged top plan view of the.

extension` cord assembly;

,Figure 31 is a bottom. plan view of the plug at the;` input end of theextension;

-Fig-ure; 4 is a sectionthrough the center of onapliig of. Figure. 2illustrating it in the associated. camera socket.;

`l53i'gure45 is an end elevatoirpartly broken away and` Iin section, ofthe plug of. Figures, 3l

Figure-6 i'swa plan view of theinside of one.. oi.

the blocks of the plug; and

'Figure 7' is a front elevation, partly broken away and in section ofthe plug at thev tripod end" of the extension.

Referringl to Figure 1, the rinvention is shown frffadapting a camerafor `use with ash gun mounted respectively on the camera. and. on vatripod, 'the Aflash* gun on the. camera .being dirre'ctedsquarely'at thesubject to rbe photographed and the tripod disposed at a suitable angleto provide such illumination vas may be considered desirable for thepicture. Figure 1 .illustrates the operator holding the camera at eyelevel while peering through the nder and a flash gun, I2 'mounted in a`socket at the top of the, camera and connected by an extensioncordindicated at I3 to a similar flash gun I4 mounted I on the tripodI5.

Preferably each of the flash guns I2 and I4 is, of the constructionillustrated in the co-pending application of Hobert W. French, Jr.,Serial No. 710,015, filed November 15, 1946, now Patent No. 2,565,492,and the camera is preferably onechaving a cooperating upper socket asillustrated in the co-pending application of James E. Harvey, Serial No.21,284, led April 15, 1948, to whichV Areference is made for furtherdisclosure of the;

socket on the camera and the ash gun holder if necessary forunderstanding of this invention.y

The extension cord comprises insulated wires. I6 and I1 connected atopposite ends to terminals in a camera attachment plug I8y and a tripodattachment plug I9 as illustrated best.

in Figure 2. The camera attachment plug vI8 (Figure 4) comprises upperand lower blocks 2I andl 22 of hard plastic material, theupper block 2|having a depending outer rim by which it is piloted and seatedon thelower block for aligning the holes through which bolts 23 extend to se.cure the blocks together.V

Interiorly, upper blockv 2I is recessed to pro-i vide within theassembly a chamber 24 for con-- nectionof the contacts andforresiliently mount@ ing the center terminal ofv the plug as will ap;-pear. Referring to Figures 3 and 4, the bottom of lower block 22comprises a recessed portion, in which is seated a metal plate 25 havingop The top of block positely projecting ears 26. 2I is, similarlyvrecessed to seat a largermetal plate 21 having oppositely projectingears 28.Y

Bolts 23 extend through' blocks 2| and 22l and.

when nuts 29 are tightened the entire plugv as,-

sembly is drawn together with bolts 23 electrically connecting the outersocket members.

At opposite sides plate 2l is bent upwardlyand then inwardly to provideslide guides 3l and 32.

Plate 21 is centrally apertured at 33 and a cenj tral metal' terminalpost 34fproject`swthroughz.

aperture 33 slightly above the surface of the plate and with sufcientclearance with aperture 33 to prevent short circuit.

Plate is centrally apertured at 35 and rigidly secured to it, as byrivets, is a metal plate 36 apertured in alignment with aperture 35 andhaving its opposite sides bent downwardly at legs 31. Legs 31 terminatein slide guide feet 39 and 4i comprising integral outward and downwardextensions of the legs. Guide feet 39 and 4l are parallel to guides 3iand 33.

An apertured metal plate 42, riveted to plates 25 and 35, has anintegral U-shaped spring leg 43 that extends parallel to the guide feetand between them for a purpose to appear. A bottom metal terminal post44 projects through aperture and plates 36 and 42 in spaced relation soas to be insulated therefrom.

Within chamber 24, the inner end of post 34 is shouldered and threadedfor removably securing thereon a wire terminal clip 45 and one end of aU-shaped metal spring blade 46, as by a nut 41. The other end of aspring 4S is riveted to the inner end of post 44 and is disposed in anarrow recess 48 in block 22 whereby rotation of spring 46 about theaxes of the posts is prevented.

Post 34 projects with a fairly close slide t through an opening 49 inblock 2i, and post 44 projects with a fairly close slide nt through anopening 5| in block 22, so that the spring connected posts 34 and 44 areguided for axial movement in the plug.

Wire i1 is connected to clip 45, and wire I6 is connected to a terminalclip '52 that is removably secured as by screw 53 to plate 2'! withinchamber 24, the wires entering the plug through a suitable sideaperture.

When the plug is assembled, with bolts 23 drawn tight, spring 46 iscompressed into its U shaped energized position shown in Figure 5 sinceits opposite legs bear respectively on the blocks 2| and 22. it will beappreciated however that both Aposts 34 and 44 may be displaced axiallyinwardly against further resilient resistance of spring 45 which tendsto keep them at their outermost projected position. Posts 34 and 44 arepreferably in axial alignment.

In Figure 4, the upper wall of the camera Ii is vindicated at 54 and isformed with a depression 55. 'A metal plate 5e is riveted to the camerawall and the sides of plate 56 are bent upwardly and inwardly to formslide guides 5l and .58 that are exactly the same shape and size asguides 3l and 32. Plate 56 and the camera wall are apertured to receivean insulating button y59 carrying a center contact Si that is in turnsecured to a lead 62 from the shutter mechanism. Lead 52 provides oneside of the line within the camera and the metal wall of the cameraprovides the other side of the line. Looking down on it the socket atthe top of the camera is substantially identical with the socket at thetop of plug I8 except that in the camera the center terminal is fixed.

Since the guides 5l and 58 provide an openV ended socket structure, theplug i8 may be mounted on the camera by sliding the plug tov withcontact 6i engaged with post 44, the latteri moving inwardly of the pluga slight distance during this mounting of the plug so that spring 45tends to resiliently urge post 44 and contact 6i together to secure thebest possible electrical contact.

The socket structure at the bottom of iiash gun I2 is the same as theguide foot and spring structure at the bottom of plug I 8 abovedescribed, so that the flash gun i2 is mounted on the plug I8 in thesame manner that plug I8 is mounted on the camera, post 34 beingresiliently urged into engagement with the flash gun socket centercontact by spring 46.

Figure 7 illustrates the plug I9 at the other end of the cord whichcomprises upper and lower blocks 63 and 64 of insulating plastic heldto- .2 gether as in block IS by through bolts 6U. The

upper socket of block i9, comprising slide guides G5 and 5S at oppositesides of terminal plate 81 are the same as slide guides 3i and 32 onblock 2 i.

A center contact post 6E extends above the level of plate 3l through asliding t aperture `6i) in block S3 and a much larger aperture H inplate Si so as to be insulated from plate 61. Within the plug, block 33is formed with a chamber 12 wherein wire terminal clips 'i3 and 74 aresecured respectively to the plate 37 by a screw (not shown but like thatat 63) and to the threaded shouldered inner end of post .63 as by nutand washer assembly l5. A coiled compression spring "it reacting betweenthe inner flat surface of block 164 and the washer on post 68resiliently urges post E8 to its uppermost position but permits suchaxial displacement of the post as may be needed to accommodate thesocket structure of the lower end of flash gun i4 which is the same asthat at the bottom of plug I8.

The wires i6 and I1 project through a suitable side opening in plug I9to connect with clips I3 and 'i4 respectively, the center contacts ofthe plugs being connected to each other and to the center contact 5| inthe camera, and the slide guides all being connected together andproviding the other side of the line.

The bottom of block 54 contains a molded in-` sert sleeve of metal Tithreaded at 78 to t with the standard screw that projects up from theconventional tripod. Obviously any other tripod attachment device may beused here.

I have thus described an extension wherein two iiash guns may be used,mounted on the camerav and a tripod respectively. It will be seen thatflash gun I4 may be held in the hand as well as on a tripod, and ifdesired the plugs at opposite ends of cord i3 may be identical so thatanother similar cord may be attached for using more than two ilash guns.The variations of the arrangement are obvious.

The invention may be embodied in other speciiic forms without departingfrom the spirit or essential characteristics thereof. The presentembodiment is therefore to be considered in all respects as illustrativeand not restrictive, the scope of the invention being indicated by theappended claim rather than by the foregoing description, and all changeswhich come within the meaning and range of equivalency of the claim aretherefore intended to be embraced therein.

What is claimed and desired to be secured by United States LettersPatent is:

An extension cord for a camera photoflash assembly comprising a pair ofinsulated electrical conductors having attachment plugs at oppositeends, substantially identical sockets on the tops of-both of said plugseach comprising parallel` slide guide elements facing toward each other1 UNITED STATES PATENTS and an insulated center contact, a socket on theNumber Name Date lbottom of one of said plugs comprising spaced 852 ,190Benjamn May 7 1907 depending parallel 'guide footrelements and an 12411106 Frydrychog; "Sept 25 1917 insulated center contact, said guidefoot elements 5 1256811107 Lee 1 Jan' 5 1926 being proportioned tooperatively fit only Within 1,632,081 Jones "June'14 1927 v a socketsimilar to one of said top sockets, means 1,741,264 Wapp''. Dec 31 1929connecting one of said conductors to al1 of said 1,812,396 Eckste1n` Jun30' 1931 center contacts, and means connecting the other 1,888,714Erikson No1/ 22 1932 of said conductors to the guide elements 0f all 0f10 1,391,112 McNeu Jan. 1o 1933 Said Sockets 2,177,409 Hummert .001. 24:1939 JOHN W- BARNES- 2,424,422 Tresise July 22 1947 REFERENCES CITED Thefollowing references are of record in the 15 le of this patent:

